Can insulin pump technology help prevent low blood sugar in patients with T1D?

This study evaluated whether the ‘suspend-before-low’ feature of automatic insulin pumps prevented hypoglycemia (HG) in patients with Type 1 diabetes (T1D). The authors concluded that this feature successfully reduced the rate of HG and was not associated with increased side effects.

The goal of treatment for patients with T1D is to lower blood glucose levels. However, long-term insulin treatment can cause blood glucose levels to become too low. This is called hypoglycemia. HG can cause further health complications. Some patients are considered at high risk of HG because they previously experienced it, or they are not aware of what it is. 

Insulin pump systems have built-in sensors that can detect blood sugars levels and administer insulin when needed. The ‘suspend-before-low’ feature in some pumps stops delivering insulin at a certain point to prevent HG. Whether this feature can help lower the risk of HG in high-risk patients with T1D is under investigation.

This study had 153 patients with T1D that were considered high-risk for HG. Patients were divided into two groups. 76 patients received insulin with the MiniMed 640G pump with the ‘suspend-before-low’ feature (intervention group). 77 patients received insulin with a pump that did not have this feature (control group). Patients were followed-up for an average of 24 weeks.

Overall, the ‘suspend-before-low’ feature was activated in the intervention group on average 2.5 times per patient per day. Overall, HG occurred 1.1 times per week for the intervention group and 4.1 times per week for the control group. The intervention group had at least a 62% reduction in HG compared to the control group.

On average, episodes of HG where blood sugar levels dropped below 54 mg/dL lasted 27.6 minutes for the intervention group and 61.8 minutes for the control group. Over 6 months, HbA1c (average blood glucose over 3 months) levels dropped by 0.16% for the intervention group and 0.25% for the control group. 

Overall, HG was experienced by 13% of the control group and 5% of the intervention group. High blood sugar levels were also reported by 9% of patients in each group. No side effects related to the pump system were reported.

This study found that the ‘suspend-before-low’ feature of the MiniMed 640G pump reduced the occurrence of HG in patients with T1D. The authors suggest that this insulin pump technology be widely used to help high-risk patients with T1D.

This study was funded by Medtronic, the manufacturer of the MiniMed 640G pump. This study also had a small number of participants and a short duration. Longer studies with more patients are needed to confirm these results.